Elastomeric compositions comprising high amounts of filler are utilized in various applications, such as in tires, where increased elasticity, hardness, tear resistance, and stiffness are desired. These enhanced properties are generally achieved by adding large amounts of hard fillers (e.g., carbon black, silica, and other minerals) to the elastomeric composition. An additional benefit of highly-filled compositions is that they can be produced on a more economic scale compared to elastomeric compositions containing little or no fillers. The elastomer components are generally the most expensive component in an elastomeric composition, thus the utilization of high amounts of filler can minimize the amount of expensive elastomer used in the elastomeric composition.
Unfortunately, the presence of high amounts of fillers in an elastomeric composition greatly increases the processing viscosity of the composition, thus making it very difficult to process. One current solution to this problem is to add a processing aid, such as an aromatic processing oil, to the elastomeric composition in order to reduce its processing viscosity. However, the incorporation of processing aids into the elastomeric compositions generally softens the cured elastomeric compositions, thereby mitigating the desired benefits of adding high amounts of filler to the composition.
Accordingly, there is a need for a highly-filled elastomeric composition that is both easily processable and that exhibits ideal elasticity, hardness, tear resistance, and stiffness when cured. In addition, there is a need for a processing aid for elastomeric compositions that can improve the processability of the elastomeric composition and also enhance its elasticity, hardness, tear resistance, and/or stiffness.